Many different types of metal enclosures exist for holding a printed circuit board (PCB) and which provide electromagnetic compatibility (EMC) by including shielding and/or by restricting the size of any holes or gaps in the enclosure to control the ability of electromagnetic radiation waves to pass through the enclosure.
Various methods of making enclosures of metal exist today. Each method has advantages and drawbacks. Enclosures formed of sheet metal are able to be formed inexpensively and are able to be provided with integral EMC shielding, such as, for example, by including electrically conductive contacts formed by stamping and/or bending portions of a flat wall. However, enclosures of sheet metal include several design limitations inherent in the process of bending and forming a thin metal sheet. Sheet metal enclosures are also generally less effective at dissipating heat than enclosures of cast metal, making them unsuitable for many applications requiring relatively high amounts of energy to be dissipated in the form of heat and without exceeding temperature thresholds. Enclosures of cast metal have historically had their own set of drawbacks including relatively wide tolerances and brittle materials. The wide tolerances and the brittle nature of traditional cast metal enclosures prevented the enclosures from being integrally formed with resiliently deflectable contacting teeth to make electrical contact between housing portions of the enclosure. Therefore, large numbers of screws or other fasteners were commonly used with such cast enclosures to minimize gaps between enclosure portions and to provide EMC shielding.
Therefore, there exists a need for an inexpensive enclosure for holding a printed circuit board that minimizes gaps between enclosure portions to prevent electromagnetic waves from propagating therethrough.